Synergistic contribution of CD14 and HLA loci in the susceptibility to Buerger disease

The Role of Gut Microbiota in Thromboangiitis Obliterans: Cohort and Mendelian Randomization Study

BACKGROUND AND AIMS

Thromboangiitis obliterans (TAO), also known as Buerger's disease, is a rare vasculitis. Observational epidemiology studies have suggested a relationship between the gut microbiota and TAO. However, due to confounding factors and reverse causality, the causal relationship remains unclear. Based on the assumption of their association, this study sought specific gut microbiota causally linked to TAO.

METHODS

The case-control study was conducted at the Xiangya Hospital of Central South University from November 2022 to January 2023 including twelve TAO patients and nine healthy controls. We conducted a Mendelian randomization (MR) study using summary statistics from a genome-wide association study (GWAS) of gut microbiota and TAO. Considering the scale and accessibility of the data, the MiBioGen consortium served as the exposure, whereas the FinnGen consortium GWAS study served as the outcome. Finally, we compared the results of the MR with those of the case-control studies.

RESULTS

The inverse variance weighted (IVW) (OR = 0.119, 95% CI: 0.021-0.688, p = 0.017) and maximum likelihood (ML) (OR = 0.121, 95% CI: 0.020-0.742, p = 0.022) estimates suggest that Ruminiclostridium 5 has a suggestive protective effect on TAO while the IVW (OR = 5.383, 95% CI: 1.128-25.693, p = 0.035) and ML (OR = 5.658, 95% CI: 1.142-28.021, p = 0.034) estimates suggest that Eubacterium (xylanophilum group) has a suggestive risk effect on TAO, and the ML (OR = 0.055, 95% CI: 0.004-0.755, p = 0.030) estimates suggest that Lachnospira has a suggestive protective effect on TAO. No significant heterogeneity of instrumental variables or horizontal pleiotropy was found. The results of the case-control study showed that the TAO had a lower relative abundance of Ruminiclostridium 5 (p = 0.015) and Lachnospira (p = 0.048), and a higher relative abundance of Eubacterium (xylanophilum group) (p = 0.029) than the healthy controls. These results were consistent with the MR analysis.

CONCLUSIONS

Our study demonstrates that Ruminiclostridium 5, Lachnospira, and Eubacterium (xylanophilum group) are causally related to TAO, suggesting their potential significance for the prevention and treatment of TAO.

Comparative Analysis of Transcriptome Profiles in Patients with Thromboangiitis Obliterans

BACKGROUND

Thromboangiitis obliterans (TAO) causes vascular insufficiency due to chronic inflammation and abrupt thrombosis of the medium and small arteries of the extremities. In our study, we aimed to determine biomarkers for the diagnosis of TAO by evaluating 15 male TAO patients with Shinoya diagnostic criteria and 5 healthy controls who did not have TAO-related symptoms in their family histories.

METHODS

The Clariom D Affymetrix platform was used to conduct microarray analysis on total RNA extracted from whole blood. A total of 477 genes (FC ≤ 5 or >5) common to the fifteen patient and five control samples were selected using comparative microarray analysis; among them, 79 genes were upregulated and 398 genes were downregulated.

RESULTS

According to FC ≤ 10 or >10, in the same TAO patient and control group, 13 genes out of 28 were upregulated, whereas 15 genes were downregulated. The 11 key genes identified according to their mean log2FC values were PLP2, RPL27A, CCL4, FMNL1, EGR1, EIF4A1, RPL9, LAMP2, RNF149, EIF4G2, and DGKZ. The genes were ranked according to their relative expression as follows: FMNL1 > RNF149 > RPL27A > EIF4G2 > EIF4A1 > LAMP2 > EGR1 > PLP2 > DGKZ > RPL9 > CCL4. Using protein-protein interaction network analysis, RPL9, RPL27A, and RPL32 were found to be closely related to EIF4G2 and EIF4A1. The Reactome pathway found pathways linked to 28 genes. These pathways included the immune system, cellular responses to stress, cytokine signaling in the immune system, and signaling by ROBO receptors.

CONCLUSIONS

By figuring out the protein expression levels of the genes that have been found to explain how TAO disease works at the molecular level, it will be possible to figure out how well these chosen transcripts can diagnose and predict the disease.

Pathological and immunological differences of arterial thrombi and wall caused by three different periodontal bacterial injections in rat models and proposals on the pathogeneses of vascular diseases

OBJECTIVES

Periodontal bacteria that have been studied show a strong connection to various vascular diseases. Among the many kinds of periodontal bacteria, Porphyromonas gingivalis (Pg) is well examined in the general aspects and in a rat model. However, whether other periodontal bacteria work or react differently is not studied well.

MATERIAL AND METHODS

We chose Aggregatibacter actinomycetemcomitans (Aa) and Prevotella intermedia (Pi) as different types of periodontal bacteria. Low-density and high-density bacterial solutions were injected in the small artery of rats' groins using our rat model. Eighteen limbs of 9 SD male rats (500-650 g) were used. After 7 days, 14-18 days, and 28 days, the rats were sacrificed. A pathological and an immuno-histochemical study was conducted and reported on the low-density group with 12 limbs because the Pi group lacked a high-density study. Immuno-histochemical staining of live Pg was performed on three limbs of three rats at 1 h, 3 h, and 1 week after injection.

RESULTS

The appearances from the acute, at 7 days, to chronic phases, at 28 days, were observed. The differences of the species were certainly observed in the internal elastic lamina (IEL), and immuno-histochemical reactions. The inflammatory reactions, such as cellular distribution or intra-thrombus materials, were similar in all. One week later, we could not see any living bacteria in the specimen or immunological observation.

CONCLUSIONS

The three species were essentially the same, except for Aa's stronger disruption of IEL, and more CD3 (Pan T cell) in Pi and more CD79a (Pan B cell) in Pg. We propose a new concept of a possible mechanism of vascular diseases, in which the work of LPS (lipopolysaccharides) and a toll-like receptor (TLR) is emphasized.

Risk Factors, Mechanisms and Treatments of Thromboangiitis Obliterans: An Overview of Recent Research

BACKGROUND

Thromboangiitis obliterans (TAO) is a nonatherosclerotic thromboticocclusive vasculitis that affects the vessels of the small and medium-sized extremities. No explicit etiology or pathogenesis of TAO has been proven, and more effective treatments are needed.

OBJECTIVE

The study aimed to summarize and present an overview of recent advances regarding the risk factors, mechanisms and treatments of TAO and to organize the related information in figures to provide a comparatively complete reference.

METHODS

We searched PubMed for English-language literature about TAO without article type limits, including articles about the risk factors, pathological mechanisms and treatments of TAO in the last 10 years with essential supplements (references over ranges and English abstracts of Russian literature).

RESULTS

After screening content of works of literature, 99 references were evaluated. We found that risk factors of TAO include smoking, gene factors and periodontal diseases. The underlying mechanism of TAO involves oxidative stress, immunity, hemodynamic changes, inflammation and so on. Moreover, similarities in genetic factors and cigarette relevance existed between periodontal diseases and TAO, so further study of relationship was required. For TAO treatment, medicine, endovascular intervention and revascularization surgery, autologous cell therapy and novel therapies were also mentioned. Besides, a hypothesis that infection triggers autoimmunity in TAO could be speculated, in which TLR4 plays a key role.

CONCLUSION

1. A hypothesis is put forward that infections can trigger autoimmunity in TAO development, in which TLR4, as a key agent, can activate immune signaling pathways and induce autoimmune cytokines expression. 2. It is suggested to reconsider the association between periodontal diseases and TAO, as they share the same high-risk population. Controlling periodontal disease severity in TAO studies may provide new clues. 3. For TAO treatment, endovascular intervention and autologous cell therapy both showed promising long-term therapeutic effectiveness, in which autologous cell therapy is becoming more popular, although more clinical comparisons are needed.

Current Trends in Epidemiology and Clinical Features of Thromboangiitis Obliterans in Japan - A Nationwide Survey Using the Medical Support System Database

BACKGROUND

The epidemiology and clinical features of thromboangiitis obliterans (TAO) in Japan have not been updated extensively.

METHODS AND RESULTS

This retrospective study used the Japanese Ministry of Health, Labour and Welfare (JMHLW) medical support system database and associated health insurance data. The number of medical financial support recipients registered as TAO patients and estimated prevalence of TAO decreased from fiscal year (FY) 2000 (10,089 and 7.95 [95% confidence interval, CI: 7.79-8.10] per 100,000 population) to FY 2010 (7,147 and 5.58 [95% Cl: 5.45-5.71] per 100,000) and leveled off until 2014. The prevalence of TAO among patients with peripheral arterial occlusive diseases declined from 7.15% (95% Cl: 7.00-7.31) in FY 2008 to 6.12% (95% Cl: 5.98-6.26) in FY 2014. Clinicodemographic features were obtained from 89 new recipients in FY 2013 and 2014: 12 (13%) women, 36 (40%) aged ≥50 years, 26 (29%) had probable onset age ≥50 years, 7 (8%) were non-smokers, and 12 (13%) had arteriosclerosis-related comorbidities. The symptoms were similar regardless of registration age, smoking history, or sex. Although 40 (45%) had digit ulcers, only 12 (13%) fulfilled Shionoya's criteria. They rarely had infrapopliteal lesions combined with upper extremity involvement or phlebitis.

CONCLUSIONS

The prevalence of TAO has decreased in Japan. In the current diagnosis of TAO, various clinical characteristics including late onset, arteriosclerotic factors, non-smoking, or mild symptoms should be considered.

Human leukocyte antigen class I (A, B) and class II (DRB1) allele and haplotype frequencies in Iranian patients with Buerger's disease

OBJECTIVE

The aim of this study was to investigate the human leukocyte antigen (HLA) class I (HLA-A and HLA-B) and II (HLA-DRB1) allele and haplotype frequencies in a group of Iranian patients with Buerger's disease (BD) in comparison with a normal healthy control group.

METHODS

A total of 70 unrelated male patients and 100 healthy controls from Sina Hospital, Tehran, Iran, belonging to the same ethnic background, were enrolled in this case-control study. HLA-A, B, and DRB1 typing were performed by polymerase chain reaction with sequence-specific primers (PCR-SSP).

RESULTS

The results of this case-control study showed that the frequency of the HLA-A*03:01 (odds ratio (OR) = 2.88, P value (Pv) = .002), HLA-A*29:01 (OR = 15.31, Pv < .001), HLA-DRB1*04:02 (OR = 3.41, Pv < .001), and HLA-DRB1*16:01 (OR = 8.16, Pv < .001) was significantly higher in BD patients compared with healthy controls, whereas the frequency of the HLA-DRB1*01:01 (OR = 0.03, Pv < .001) was significantly lower in BD patients. The most frequent extended haplotypes in our patients were HLA-A*02:01-B*55:01-DRB1*04:03.

CONCLUSION

This study is the first study evaluating an association between the HLA pattern and BD in the patients with BD from North West and North Iran.

Cilostazol on the expression of ICAM-1, VCAM-1 and inflammatory factors in plasma in patients with thromboangiitis obliterans

The effects of cilostazol on the expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and inflammatory factors in plasma in patients with thromboangiitis obliterans (TAO) were studied. Plasma viscosity, fibrinogen, total cholesterol (TC) and triglyceride (TG) were detected for the healthy control, TAO and cilostazol groups, respectively. Results showed that compared with those in the control group, the plasma viscosity, fibrinogen, TC and TG levels in TAO group were significantly increased. By contrast, compared with those in TAO group, the plasma viscosity, fibrinogen, TC and TG levels in the cilostazol group were significantly decreased. ELISA results revealed that ICAM-1 and VCAM-1 expression levels in TAO group were obviously increased compared with those in control group. ICAM-1 and VCAM-1 expression levels in cilostazol group were obviously decreased compared with those in TAO group. According to RT-PCR, the mRNA expression levels of IL-1β, IL-6 and TNF-α in TAO group were significantly higher than those in control group, while the levels in cilostazol group were significantly decreased compared with those in TAO group. In addition, RT-PCR and western blotting proved that expression of both mRNA and protein of ICAM-1 and VCAM-1 in TAO group was significantly increased and obviously decreased after administration of cilostazol. The results of analysis of variance showed that the differences of ICAM-1 and VCAM-1 expression was statistically significant among the control, TAO and cilostazol groups (p<0.01). Cilostazol can significantly reduce the TAO-induced abnormal increase in ICAM-1, VCAM-1 and inflammatory factor expression in plasma in patients. It was proven that cilostazol has a good anti-TAO effect.

Pathogenesis of thromboangiitis obliterans: Gene polymorphism and immunoregulation of human vascular endothelial cells

Thromboangiitis obliterans (TAO) is a nonatherosclerotic, segmental, inflammatory vasculitis, which commonly affects the small- and medium-sized arteries of the upper and lower extremities. Despite its discovery more than a century ago, little progress has been made in its treatment. Unless the pathogenesis is elucidated, therapeutic approaches will be limited. The purpose of this review article is to collate current knowledge of mechanisms for the pathogenesis of thromboangiitis obliterans and to propose potential mechanisms from a genetic and immunoreactive point of view for its inception. Therefore, we discuss the possibility that the pathogenesis of this disease is due to a type of gene polymorphism, which leads to an immunological inflammatory vasculitis associated with tobacco abuse, highly linked to T cells, human vascular endothelial cells (HVECs), and the TLR-MyD88-NFκB pathway, distinct from arteriosclerosis obliterans and other vasculitides.

Association Between Three SNPs and Thromboangiitis Obliterans in Xinjiang Uyghur Population

BACKGROUND

Thromboangiitis obliterans (TAO), also called Buerger's disease, is a chronic peripheral vascular occlusive disease. It is an obliterative vasculitis characterized by arterial thrombosis and strongly associated with tobacco exposure. The pathogenesis and etiology of TAO are not well understood, but genetic factors may be important in its development. A case-control study was undertaken to identify genetic factors potentially involved in the pathogenesis of TAO in a Xinjiang Uyghur population of China, where TAO is common.

METHODS

We ascertained 177 TAO patients by clinical screening and 86 healthy individuals from the HAPMAP database. The genotypes of single-nucleotide polymorphisms (SNPs) of the participants were identified using the Affymetrix Genome-Wide Human SNP Array 6.0 to perform a genome wide association study (GWAS). The association between the SNPs and incidence of TAO was quantified using race stratification exposure.

RESULTS

Through a case-control GWAS study 26 SNPs were significantly associated with incidence of TAO following a Bonferroni correction. However, after genomic control correction for population stratification only three of these SNPS were highly significantly associated with TAO: rs376511 in IL17RC (OR = 24.4, 95% CI:8.68 - 68.62, p < 0.0001), rs7632505 in SEMA5B (OR = 29.47, 95% CI:7.16 - 121.3, p < 0.0001), and rs10178082 (OR = 18.09, 95% CI: 6.56 - 49.92, p < 0.0001) showed a significant risk of TAO in the Uyghur population.

CONCLUSIONS

This study shows an association between these 3 SNPs and susceptibility to TAO in the Uyghur population, suggesting that polymorphisms in the IL-17RC and Sema 5B genes may pre-dispose individuals in this population to development of TAO. These findings require replication.

The Epidemiologic and Clinical Findings of Patients with Buerger Disease

BACKGROUND

Buerger disease is a nonatherosclerotic peripheral arterial disease, which is mostly observed in young male smokers. Buerger disease is characterized by the observation of peripheral arterial occlusion by angiography. The condition may be caused by microembolization in the small-sized arteries of the distal extremities. Buerger disease is diagnosed based on the Shionoya's clinical diagnostic criteria, which include: (1) a history of smoking, (2) onset before the age of 50 years, (3) the presence of infrapopliteal arterial occlusions, (4) either upper limb involvement or phlebitis migrans, and (5) the absence of atherosclerotic risk factors other than smoking. Several studies have reported that oral bacterial infections (periodontitis) could activate the onset of Buerger disease. In this study, we report the epidemiologic and clinical manifestations of patients with Buerger disease.

METHODS

Fifty-eight patients who were surgically treated between July 1989 and June 2014 at Tokyo Medical and Dental University Hospital were enrolled in this study. All of the patients clinically diagnosed with Buerger disease based on Shionoya's clinical diagnostic criteria. Fifty-five male and 3 female patients were treated. The mean age of the patients was 48 years (range, 21-73 years).

RESULTS

All of the patients were either smokers or had a history of smoking. The mean Brinkman index score was 780 (range, 150-1,640). Their mean age at the onset of Buerger disease was 38 years (range, 21-50). The arterial lesions extended to the femoral arteries in 25% of cases, to the iliac arteries in 8% and to the abdominal aorta and/or visceral arteries in 6% of cases. Upper limb involvement, including cyanosis, paleness, and gangrene, was obvious in 84% of patients, and phlebitis migrans was recognized in 34%. The lower extremities symptoms involved intermittent claudication in 23% of the patients, rest pain in 13% of the patients, and ulceration or gangrene in 64% of the patients. Fifteen patients had undergone surgical arterial reconstruction, 4 patients had received endovascular therapy, 33 patients had undergone lumbar sympathectomy and 8 patients had undergone thoracic sympathectomy. Twenty percent of the patients needed minor limb amputations, and 4% required major limb amputations. In the patients who were examined for their oral conditions, periodontitis corresponding to grades B (moderate periodontitis), C (severe periodontitis), and D (edentulous patients) was revealed in 31%, 56%, and 13% of the patients, respectively.

CONCLUSIONS

More than half of the Buerger disease patients in this study were suffering from severe periodontitis. It is possible that not only the cessation of smoking, but also the improvement of periodontal care could improve the clinical symptoms related to Buerger disease.

A review on thromboangiitis obliterans pathophysiology: thrombosis and angiitis, which is to blame?

A century has passed since thromboangiitis obliterans (TAO), or Buerger's disease, was first described, but the etiology remains unclear. It is still uncertain as to whether thrombosis or vascular inflammation is the first event. TAO is an episodic inflammatory and thrombotic-occlusive vascular disease of unknown origin. The involvement of the distal vessels and nerves within the neuro-vascular bundles occurs almost always in legs and occasionally in arms. The cumulative data demonstrate that at the cellular and molecular levels, at least four main components of inflammatory reactions, including endothelial cells, platelets, leukocytes and sensory neurons, might be involved in TAO pathogenesis. The interactions among these cells in an altered microenvironment of small- and medium-sized vessels may also orchestrate the onset of TAO events. In this review, the factors that may promote thrombosis and angiitis are reconsidered at three levels: (1) host characteristics such as male gender and genetic background; (2) probable triggers including cigarette smoking and infectious agents; and (3) environmental factors such as chronic anxiety and mental stress as a consequence of low socioeconomic status. At each level, the interactions among vascular endothelium, platelets, leukocytes and sensory neurons are discussed.

Thromoboagiitis Obliterans (TAO)

Thromboangiitis obliterans (TAO) is nonatherosclerotic inflammatory disease of the peripheral blood vessels, and TAO affects the small and medium sized vessels of the extremities. TAO is mainly seen in young males who smoke, and smoking is strongly associated with the disease course and progression. The diagnosis is made on the basis of the history, the physical examination and the clinical diagnostic criteria. As the bedrock for treating patients with TAO, absolute abstinence from tobacco is most important factor, and patients with TAO are usually managed conservatively. Surgical bypass or endovascular therapy is usually not possible for patients with TAO because of the diffuse segmental involvement and the distal nature of the disease. Therefore, stem cell therapy is considered to be a novel therapeutic modality for treating patients with TAO and who are not eligible for conventional revascularization therapies. In this paper, I have summarized the recent knowledge about TAO and I have reviewed the recent studies that have focused on the treatment of TAO.

Thromboangiitis obliterans in two brothers

Two brothers (case 1 and case 2) with erythema nodosum were diagnosed with thromboangiitis obliterans (TAO). The patients were treated with compounds including Danshen Dripping Pills, Fufang Danshen Diwan and Salvia tetramethylpyrazine. The patients were also treated with fibro-blast growth factor to promote epidermal growth and Bayaspirin enteric-coated tablets to reduce platelet aggregation. The polysaccharide nucleic acid fraction of Bacillus Calmette-Guérin and compound glycyrrhizin tablets were taken to improve immune function. Following treatment, case 2 had reduced pain levels in the left foot. The ulcer on the first toe of the left foot had decreased in size, with a reduction in pus secretions and inflammation. Case 1 demonstrated a reduction in pus secretion from the ulcer. However, the area of the ulcer had increased, spreading to the fifth toe with gangrene. A tendon had become exposed on the right foot, which was broken and induced severe pain.

Thromboangiitis Obliterans (Buerger's Disease)-Current Practices

Thromboangiitis obliterans (TAO) is a nonatherosclerotic, segmental inflammatory disease that most commonly affects the small and medium-sized arteries and veins in the upper and lower extremities. Cigarette smoking has been implicated as the main etiology of the disease. In eastern parts of the world TAO forms 40-60% of peripheral vascular diseases. Clinical features and angiographic finding are the basis of early diagnosis of TAO. Abstinence from smoking is the only definitive treatment to prevent disease progression. Medical management in form of aspirin, pentoxyfylline, cilostazol, and verapamil increase pain-free walking distance in intermittent claudication, but long term usage fails to prevent disease progression in patients who continue to smoke. Surgical treatment in form of revascularization, lumbar sympathectomy, omentopexy, and Ilizarov techniques help reduce pain and promote healing of trophic changes. Newer treatment modalities like spinal cord stimulation, prostacyclin, bosentan, VEGF, and stem cell therapy have shown promising results. Latest treatment options include peripheral mononuclear stem cell, and adipose tissue derived mononuclear stem cells have been shown to be effective in preventing disease progression, decrease major amputation rates, and improving quality of life.

The role of autoimmunity in thromboangiitis obliterans (Buerger's disease)

Thromboangiitis obliterans (TAO), or Buerger's disease, is a nonatherosclerotic segmental vasculitis that affects the small- and medium-sized arteries and veins of the extremities and is strongly associated with tobacco exposure. The immunopathogenesis of TAO remains largely unknown. In the acute phase of the disease, macrophages and occasional giant cells are observed in the characteristic intraluminal thrombus with a relatively mild infiltration of CD4(+) and CD8(+) T cells and macrophages in the internal lamina. VCAM-1, ICAM-1, and E-selectin expression on the surface of vascular endothelial cells is increased. A variety of circulating autoreactive antibodies targeting endothelial cells and vessel wall components are associated with active disease. One recent report suggests that removal of circulating antibodies by immunoadsorption may decrease disease severity. TAO has been associated positively and negatively with various MHC class 1 and 2 genes; however, genetic testing is not currently used for clinical diagnosis or management. The possible links between tobacco exposure and loss of tolerance for vascular tissues, current management strategy for patients with TAO, and opportunities for translational science are discussed.

E-selectin mediates Porphyromonas gingivalis adherence to human endothelial cells

Porphyromonas gingivalis, a major periodontal pathogen, may contribute to atherogenesis and other inflammatory cardiovascular diseases. However, little is known about interactions between P. gingivalis and endothelial cells. E-selectin is a membrane protein on endothelial cells that initiates recruitment of leukocytes to inflamed tissue, and it may also play a role in pathogen attachment. In the present study, we examined the role of E-selectin in P. gingivalis adherence to endothelial cells. Human umbilical vein endothelial cells (HUVECs) were stimulated with tumor necrosis factor alpha (TNF-α) to induce E-selectin expression. Adherence of P. gingivalis to HUVECs was measured by fluorescence microscopy. TNF-α increased adherence of wild-type P. gingivalis to HUVECs. Antibodies to E-selectin and sialyl Lewis X suppressed P. gingivalis adherence to stimulated HUVECs. P. gingivalis mutants lacking OmpA-like proteins Pgm6 and -7 had reduced adherence to stimulated HUVECs, but fimbria-deficient mutants were not affected. E-selectin-mediated P. gingivalis adherence activated endothelial exocytosis. These results suggest that the interaction between host E-selectin and pathogen Pgm6/7 mediates P. gingivalis adherence to endothelial cells and may trigger vascular inflammation.

Clinical Study of Phlebitis Migrans and Incompetence of the Leg's Superficial Vein in Buerger Disease

Three of four (75%) vein biopsy samples from four patients (all male, mean onset: age 33.0, mean biopsy: age 59.7) of chronic phase phlebitis migrans showed positive periodontal bacteria DNA under the PCR (polymerase chain reaction) method. Of the 24 cases of Buerger disease (22 males, 2 females, mean onset: age 31.9, mean examination: age 62.6) that were investigated in our vascular laboratory, 65% of the patients suffered from moderate to severe varicose veins. Eight cases had a history of phlebitis migrans and three had an active ulcer or uncontrollable erosion in the foot. The rate of incidence was significantly higher than that of the well-matched control group. Other findings included one instance of deep vein thrombosis, and one instance of deep vein reflux. We could suggest that some intractable ulcer or erosion cases of Buerger disease may be complicated by superficial vein incompetence or other deep vein insufficiency. We also we need to check Buerger disease patients with duplex for vein reflux and other insufficiencies. Treatment of the varicose veins (including elastic stockings) was effective for all of the patients. (English Translation of Jpn J Phlebology 2011; 22: 25-31.).

Are There Any Objections against Our Hypothesis That Buerger Disease Is an Infectious Disease?

In 1878, Winiwarter used a microscope and reported a case of 57 year-old man demonstrating Buerger disease. After that, 134 years passed. Leo Buerger and Edgar V. Allen strongly suggested that Buerger disease is an infectious disease without any doubt. Also, an etiologic point is the luminal infectious thrombus, which is thought to be the core of the disease. Many etiological factors were proposed and then discarded after academic scrutiny, but two big discoveries were made in 2005 and 2008. Namely, periodontal bacteria DNA was found in the occluded arteries of 93% of patients with Buerger disease, and periodontal bacteria (typical weak bacteria) were found to dwell in the platelets. Using these evidences, supported by genetic and epidemiological facts, we could almost explain the pathogenesis or clinical course of Buerger disease, which had been already studied.

A single nucleotide polymorphism in the 3'-untranslated region of MyD88 gene is associated with Buerger disease but not with Takayasu arteritis in Japanese

Buerger disease (BD) and Takayasu arteritis (TA) are rare vascular disorders. Although their etiology and pathogenesis have not been elucidated, several studies have suggested the involvement of innate immunity. Myeloid differentiation primary-response protein 88 (MyD88) is a key signaling adaptor for all Toll-like receptors, which have a central role in innate immunity. In the present study, we evaluated the association of MyD88 with BD and TA. We conducted case-control studies in Japanese populations composing of 131 BD cases, 90 TA cases and 270 healthy controls to be genotyped for a single nucleotide polymorphism rs7744 A>G in the 3'-untranslated region of MyD88 gene. The frequency of GG genotype was significantly lower in the BD patients than in the controls (6.9 vs 15.9%, P=0.011, odds ratio=0.39, 95% confidence interval; 0.19, 0.81), although there was no significant difference in the genotype frequencies between the TA patients and controls. It was suggested that MyD88 may confer resistance to BD in Japanese. Because this is the first report of the association between MyD88 and BD, replication studies in other cohorts are required.

Periodontal bacteremia and various vascular diseases

BACKGROUND AND OBJECTIVE

Weak oral bacteria, such as periodontal bacteria, have been found in various vascular lesions, including atheroma, the thrombus of the occluded artery of Buerger's disease, the abdominal aortic aneurismal wall and varicose veins. Serum titer levels of each bacterium are now available and have shown a significant relationship between severity and individual differences.

MATERIAL AND METHODS

The Medline and Tokyo Medical and Dental University databases were searched to identify the literature currently available on oral bacteria and vascular diseases.

RESULTS

It is estimated that lymph vessel openings trap bacteria en route from the mouth to the bloodstream and then carry them to the vein of the venous angle near the supraclavicular area. In the case of periodontal bacteria, a typical bacterium, such as Porphyromonas gingivalis, strongly activates platelets and makes them mass, including the bacteria without phagocytosis. Simultaneously, cytokines and serotonin are discharged. Platelet engulfment was clearly demonstrated by electron microscopy analysis. An animal study using rats showed the formation of a small arterial thrombus after continuous intravenous infusion of P. gingivalis for 2-4 wk.

CONCLUSION

Weak oral bacteria, such as periodontal bacteria, may play an important role in the development of various vascular diseases, such as Buerger's disease, atherosclerosis and varicose veins, through bacteremia.

Thromboangiitis obliterans in the 21st century--a new face of disease

Thromboangiitis obliterans (TAO) is a relatively rare disease of peripheral blood vessels, affecting small and medium sized arteries and veins. Although the first description of the disease was given by Winiwarter almost 130 years ago, etiology of TAO remains not elucidated. Smoking is considered as a precipitating factor of the disease. We emphasised some particular features of the new face of TAO - significant decrease in incidences, increased disease prevalence among women and coexistence of other than smoking atherosclerotic risk factors (especially disturbances of glucose metabolism). Contemporary methods of treatment were also discussed.

Improvement of cardiac function after granulocyte-colony stimulating factor-mobilized peripheral blood mononuclear cell implantation in a patient with non-ischemic dilated cardiomyopathy associated with thromboangiitis obliterans

Cardiac involvement is a rare complication with thromboangiitis obliterans (TAO). We report a 29-year-old man with TAO accompanied with non-ischemic dilated cardiomyopathy. He had no history of heart disease, but echocardiogram demonstrated diffuse hypokinesis and dilated left ventricle. Coronary angiography revealed no organic stenotic lesion. For limb salvage, he was treated with granulocyte-colony stimulating factor (G-CSF)-mobilized peripheral blood mononuclear cell (PBMNC) implantation on his right leg. Not only ischemic leg symptoms, but also plasma level of BNP and (123)I-metaiodobenzylguanidine scintigraphic parameters improved after 24 weeks. G-CSF-mobilized PBMNC implantation could be an effective approach to treating non-ischemic cardiomyopathy.

Buerger disease, smoking, and periodontitis

Weak oral bacteria such as periodontal bacteria or Chlamydia pneumoniae have been observed in various arterial and venous lesions with epidemiological data reported prior to the discovery of bacterial invasion into vessels. Rich lymph vessels easily bring the bacteria from the mouth to the neck and the venous angle, which is directly open to the blood vessels. Periodontal bacteria travel within platelets and Chlamydia pneumoniae can be carried by monocytes. The transportation system of other weak oral bacteria have not been determined. Periodontal bacteria, especially P. gingivalis aggregate platelets and form thrombi. At the same time, secretions such as serotonin, various cytokines, and adhesion factors also appear in the blood. The characteristics of arterial lesions are dependent on the age of the patient and the condition of the endothelial cells. In young patients, infectious incidents occur due to embolic mechanisms in Buerger disease or adhesion to the superficial veins valves in varicose veins. In older patients, incidents result in adhesion in the proximal aorta, coronary arteries, or large arteries. The hypothesis here unifies the evidence on vessel lesion development and explains the possible discrepancy between vascular diseases.